Switching power supplies are popular for high power applications because of their high efficiency and the small amount of area/volume they require. Popular switching supply topologies include buck, boost, buck-boost, forward, flyback, half-bridge, full-bridge, and SEPIC topologies. Buck converters are particularly well suited for providing the high current at low voltages needed by today's high performance integrated circuits such as microprocessors, graphics processors, and network processors. Buck converters are typically implemented with active components such as a pulse width modulation controller IC (PWM), driver, power MOSFETs, and passive components such as inductors, transformers or coupled inductors, capacitors, and resistors.
The active components may be integrated, partially integrated (e.g., just the drivers and MOSFETs), or discrete. For today's highest current applications, the active components are typically discrete due to the difficulty in thermal and electrical design of a fully integrated stage. However, the capability or integrated power supply stages has begun to approach and may surpass the capability of discrete components, as more advanced and specialized semiconductor processes are developed for this type of application.